Gas generator for air bag and air bag apparatus

• US 7,207,597 B2
• Filed: 12/22/2005
• Issued: 04/24/2007
• Est. Priority Date: 10/04/1999
• Status: Expired due to Term

• Current Assignee: Daicel Chemical Industries Limited
• Original Assignee: Daicel Chemical Industries Limited
• Inventors: Ohji, Nobuyuki, Iwai, Yasunori, Katsuda, Nobuyuki, Nakshima, Yoshihiro
• Primary Examiner(s): Ilan; Ruth
• Application Number:
  US11/313,936
• Publication Number:
  US 20060131853A1
• Time in Patent Office: 488 Days
• Field of Search: 280/736, 280/737, 280/741, 280/742, 102/530, 102/531
• US Class Current: 280/742
• CPC Class Codes: B60R 2021/2633 with a plurality of inflation levels
• CPC Class Codes: B60R 2021/2648 comprising a plurality of combustion chambers or sub-chambers
• CPC Class Codes: B60R 21/2644 using only solid reacting substances, e.g. pellets, powder

Abstract

When a gas generating agent 9a inside a first combustion chamber 5a is burnt, a gas generating agent 9b is prevented from being burnt by function of a metal thin plate 11 closing a communication hole 10 with a second combustion chamber 5b. A cup 1190 having a hole 1191 is covered on an igniter 1112, and the flame thereof advances into a transfer charge 1116 straightly in a narrow width. Accordingly, since the transfer charge 1116 is burnt completely, sufficient flame for burning a gas generating agent 1109 can be generated securely. A communication hole 3010 between a first combustion chamber 3005a and a second combustion chamber 3005b is closed by double-layered seal tape 3011 laminated through an adhesive layer. After activation, the seal tapes 3011 are not ruptured due to increase in the internal pressure of the first combustion chamber 3005a, but they are peeled off easily due to increase in the internal pressure of the second combustion chamber 3005b.

Claims

1. A gas generator for an air bag comprising a housing having a gas discharge port, ignition means to be actuated by impact, and gas generating means which is to be ignited and burnt by the ignition means for generating a combustion gas to inflate the air bag,

wherein gas generating means is stored in a first combustion chamber and gas generating means is stored in a second combustion chamber with a communication hole for allowing communication between the chambers being also provided in the housing, and the communication hole between the first combustion chamber and the second combustion chamber is closed by a plurality of metal thin plates layered through an adhesive, said plurality of metal thin plates being selected so that that they are not broken as a result of combustion in the first combustion chamber but are peeled off or broken as a result of combustion in the second combustion chamber.

2. A gas generator for an air bag according to claim 1, wherein the total thickness of said plurality of metal thin plates layered except for the adhesive is in the range of 10 to 200 μ

m.

3. A gas generator for an air bag according to claim 1, wherein the thickness of each metal thin plate is in the range of 5 to 100 μ

m.

4. A gas generator for an air bag according to claim 1, wherein the thickness of a first adhesive layer provided on a contacting surface between a peripheral edge portion of the communication hole and a first metal thin plate is in the range of 10 to 50 μ

m.

5. A gas generator for an air bag according to claim 1, wherein the thickness of a second adhesive layer provided on a contacting surface between a first metal thin plate and a second metal thin plate is in the range of 10 to 50 μ

m.

6. A gas generator for an air bag according to claim 1, wherein the communication hole is closed by the metal thin plates from the side of the inner wall of the first combustion chamber.

7. The gas generator for an air bag according to claim 1, wherein the metal thin plates are made of stainless steel.